The Manchester United manager, Sir Alex Ferguson, took a single, deep breath of air in the tunnel before propelling himself one final time towards the gaze of his adoring fans. No matter that he had never graced the Old Trafford pitch in the way of his greatest players – David Beckham and Eric Cantona, Ryan Giggs and Paul Scholes, Wayne Rooney and Robin van Persie. All eyes, this day of days, were on him.

Sir Alex Ferguson applauds the fans. Photograph: Phil Noble/Reuters

To the thousands on the terraces and beyond, the often irascible Scot had been their beloved Fergie, the wily footballing genius who for decades had fashioned a succession of world-beating teams.

From all over Europe, and as far afield as America, China and Thailand, they came to pay homage before he finally steps into retirement.

Two Thai businessmen, Po Aiyara, 31, and Toto Vora, 44, had spent £2,000 for their dash to Britain to see Ferguson's last day in charge at Old Trafford.

"We both wanted to be here," said Vora. "This is a day of history. Sir Alex has been the best manager of the best club in the world."

The Sivertsen family from Norway had booked their tickets for the match in September. "It is a big, big day," said Glenn Sivertsen, ushering his wife, Monica, and the couple's sons, Tobias, 14, and Mats, 10, towards the United Megastore. "Fergie was the best, and I feel privileged to be here. We all do."

"It's the end of an era," said Kate Scholes, 33, who had come to watch Fergie's farewell with her father, Martin. "He's the only United manager I've ever known. I was a little girl when I came to my first match at Old Trafford, and I've followed him and his teams for all that time. He's been a huge part of my life."

Scholes, an architect, from Putney, south-west London, said: "I've come up today because I felt I had to. There was no choice about it. I just had to come to say goodbye to him."

For her father, there was the added melancholy of a second farewell – to his namesake. Paul Scholes, United's diminutive, talismanic midfielder, had timed his own retirement with a skill equal to his off-the-pitch shyness. Martin Scholes, 66, a retired accountant, from Mold, north Wales, was just thrilled to see him in the side.

"I suppose there's an affinity because of the name, but I've followed him right from the start and he's always been a great little player," he said.

Many of the fans had arrived early, oblivious to the rain, snapping up hastily prepared banners and authentically blotchy Ferguson face masks as they passed the long lines of burger bars outside the ground. Dominic Patel, 24, an electrical engineer, had got a friend to make him a huge laminated banner declaring his emotional response to Ferguson's departure. "Thank you for 26 years, 38 trophies," it read. And then below: "Ferguson's Red Army".

"It should have cost £60, but my mate did it for £30," he said from his front row seat. "I've had people offering stupid money for it, but it's mine. It's precious. I'll never get rid of it."

Other banners lauded United's outgoing manager as "the godfather of football". One declared: "Every single one of us loves Alex Ferguson." Another read: "The most successful manager in English football history."

Spencer Winterbottom, 44, an Old Trafford trader from boyhood, had managed to sell his fair share of banners, scarves and face-masks. "I used to be a car minder as a kid, just so I could make enough money to come into the ground. I'm working today, but that's not going to stop me paying homage to the man.

"He's done us proud as a manager himself, and now he's lined up his protege for us in David Moyes. I reckon he planned that from day one. He's a genius."

A few yards from the Munich clock, the memorial to the victims of the 1958 air disaster, Ian McGill, 58, a haulage contractor from Bristol, was explaining its significance to his grand-daughters, Bonnie, eight, and Milly, seven. "Sir Alex has had a fantastic career, and he deserves a very happy retirement," said McGill. "I'm delighted he's staying on as an ambassador for the club."

Leanne Smith, 29, a PE teacher from Stockport, felt she was in the presence of greatness. "I've been a United fan for ever," she explained. "Probably since I was conceived, because my dad's a red and my grandfather's a red."

And Ferguson?

"He's a god, and I know I'm going to cry because, for all the celebrations, it's a sad, sad day to know he's leaving. He was a one-off. The greatest ever."

Harry Atkins, eight, from Chadderton, Oldham, had arrived with his face painted with the club initials and the figure 20. "For the 20 times they've won the league title," he said.

His father, Craig, 43, a company director and season ticket holder, had just heard the news of Manchester City boss Roberto Mancini's reported departure: "Typical City," he said. "They always seem to just implode. At United, we look after people; we're a family. And I think that's why we do so well."

As the match edged towards Fergie time, those notorious seconds that referees tend to add when the Scot is parading on the touchline and United are in need, the fans waved their banners joyously in tribute to their idol – and raised their voices to mock their longtime foes the other side of the city.

"Mancini, woah, Mancini, woah," went the chant. "We've won the trophy back – and now you've got the sack."

On a giant banner outside the ground, the figures of five triumphant United players overlooked the statue of another legendary Old Trafford manager, Sir Matt Busby.

The message may well inspire Moyes, the man chosen to follow Fergie – and strike fear into the rest of the Premier League. In bold white letters it declared simply: "To be continued."